1. Field of the Invention
The present invention relates to a method and system for generating behavioral models through physical component measurement. More particularly, the present invention provides an automated method and system for generating behavioral models compatible with signal integrity simulation software.
2. The Background Art
Creating behavioral models is a time-consuming process. Often, various tools are manually used to collect data which can then be used to create a behavioral model. These tools may include power supplies and oscilloscopes.
Power supplies, logic analyzers and oscilloscopes are typically used to verify and test digital circuits. However, manually using these tools for collection of data is a time-consuming process. A need exists for an automated method and system for controlling hardware and creating a behavioral model from measurements acquired using this hardware.
A behavioral model describes behavioral characteristics of a system according to inputs and corresponding outputs. For example, a behavioral model may be defined according to specified voltages placed at various input pins and corresponding voltages produced at corresponding output pins. In comparison, a functional model, in addition to providing such behavioral characteristics, includes circuit implementation details which are often considered to be proprietary in nature. For example, a functional model may include the components used to achieve specified behavioral characteristics, such as a NAND gate, as well as a description of pin connections among the specified components.
In addition to being time-consuming, the creation of behavioral models is often performed using output created by running a SPICE or similar computer simulation. However, in order to run a SPICE simulation, such as HSPICE, functional models of actual circuits are required. A system designed to create behavioral models without using a functional model would be desirable, since chip vendors and chip foundries are generally reluctant to provide such proprietary functional model information to their customers.
The final format of a behavioral model is often as important as the process used to create the behavioral model. One disadvantage of many behavioral models is that they are often encrypted to provide protection against unauthorized duplication or translation. Encryption is not desirable, since encrypted models cannot be modified by a customer at a later date. Accordingly, a need exists for a system for creating behavioral models which may be altered by the customer on an as-needed basis.